MEMS (Micro-Electro-Mechanical System) microphones, whose active microphone structure is fashioned in a layer construction on a substrate, are known in practice. They usually detect acoustic pressure in the form of a change in capacitance between the acoustically active diaphragm and the largely rigid counter-element. The quality of the microphone signal depends essentially on the size and situation of the rear-side volume relative to the diaphragm. If bypass openings, or also web-type spring elements, are fashioned as diaphragm suspension in the edge region of the diaphragm, the connecting opening between the diaphragm and the rear-side volume should, as far as possible, extend only over the closed center region of the diaphragm in order to avoid an acoustic short-circuit. On the other hand, the attenuation of the microphone signal depends essentially on the size of the connecting opening and of the rear-side volume, so that these must have a minimum size in order to achieve a particular microphone sensitivity.
In order to realize the rear-side volume, it is known to use a rear-side etching process to etch through the substrate down to the active microphone structure. The rear-side volume is then terminated by mounting the component on a bearer, such as on a circuit board or in a housing.
In many respects, this variant turns out to be problematic. For example, the rear-side etching process must be matched very precisely to the situation, dimensions, and design of the microphone structure on the front side of the substrate. The etching front of the rear-side etching process should meet the closed diaphragm surface of the microphone structure very precisely in order to achieve the highest possible microphone sensitivity. This requires a very expensive and precise adjustment of the rear-side etching mask relative to the microphone structure on the front side of the substrate. Moreover, for the rear-side etching process only etching processes may be selected that produce a very precise reproduction of the etching mask. However, these processes mostly have a rather low etching rate. The known production process for components of the type named above is therefore relatively time-intensive and liable to error.